Haunted house ideas?

Some rooms offer their own themes. A music room can become host to an orchestra of the damned. Folks dressed as ghosts, zombies, and skeletons carrying instruments and being conducted by a skeleton or a devil. You could have a general soundtrack and have the folks appearing to play without really playing. This would be a little more of a calm room between scares, though you could of course figure out ways for the "musicians" to scare folks such as abandoning their seats and trying to force folks to take their place.

A science class room is a perfect scare room. It could become a mad scientist's laboratory or a makeshift operating room, or a morgue and autopsy. A mad scientist's lab would probably be best. Get some jars and fill them with colored water, or maybe a combination of oil and vinegar with different colors. Put fake brains, eyeballs, sausage casings filled with a little water for intestines (natural casing are intestines), hearts, fingers, hands, feet, frogs, rats, bats, etc. in the jars (you want folks to see what's in the jars so not too much food coloring that the liquid is too dark but not too little that it's real easy to see how fake something may be either). Set up beakers so they bubble (maybe use a little dry ice). Various skeletons of animals and people dot the room. Have a Jacob's Ladder set up if possible. Get some Van de Graaff generators, the kind known as plasma balls would be perfect, and set them up. On one or more tables have the scientist's experiments. If doing multiple experiments have one be a dummy while one or more experiments are real people who either "come to life" and go after folks or who are screaming for help. And the mad scientists and his assistant/assistants are ready for more subjects.

Got a home economics room? It becomes a kitchen of questionable reputation. Their cooking in their all right, rat, cat, bat, snake, and, worst of all, humans. Have things like carrots and pretzel rods thrown into food processors and the food processors get turned on on pulse as people come through. Blenders are pureeing strange concoctions. Awful smells are coming from the stoves. Cooks are chopping up things for the "meal." There's blood and guts everywhere cause the cooks just don't care what might be getting into the food. There's pot's with hands and feet sticking out of them (throw in dry ice or get a mister/fogger and put in the pot with some water so steam rises off the pot and really looks like you're cooking). Cooks chase folks with fake knives, declaring they need more meat for the meal.

A shop classroom has lovely power tools. Set up all kinds of fake arms, legs, ands, feet, fingers to look like accidents with the power tools. If you can, make some foam saw blades for table saws and miter saws using craft foam you can actually attach to the saws and have spin. If not, try to make just enough of a saw blade for table saws so it can be seen sticking up to be mistaken for a running blade. Remove all blades and drill bits and run the machines. Maybe have just one saw with an actual blade in it that's going to cut into wood or metal and have the person using it (they must be extremely careful not to do this for real) briefly cut into the wood or metal then throw a fake hand or fingers on the ground and scream how they just cut off their own hand/fingers.

Jacob's Ladder

http://youtu.be/aGjWk9HjkGI?t=1s